Eosinophilic granulomatous inflammation and multi-organ involvement probable caused by Paragonimus heterotremus infection in a pediatric patient: a rare case report.

BACKGROUND: Paragonimus heterotremus is a parasitic flatworm endemic to Southeast Asia that causes pulmonary and extrapulmonary infections. While more common in adults, pediatric cases are rare and often present atypically, posing diagnostic challenges. Eosinophilic granulomatous inflammation due to parasitic infection is especially difficult to identify in children. CASE PRESENTATION: A 9-year-old female child initially exhibited subcutaneous swelling and notable peripheral blood eosinophilia, resulting in two hospital stays without a conclusive diagnosis. Upon admission to our center, laboratory results showed increased white blood cell count, hemoglobin, platelets, and persistent eosinophilia, along with a significantly increased total IgE levels. Imaging revealed granulomatous inflammation in the skin and lungs with mild pleural effusion. Despite negative parasitic serology, a newly developed umbilical mass during hospitalization was surgically excised. Anatomopathological examination and metagenomic next-generation sequencing (mNGS) supported a probable diagnosis of P. heterotremus infection. CONCLUSIONS: This case highlights the diagnostic challenges of pediatric eosinophilic granulomatous inflammation due to rare parasitic infections, particularly in non-endemic areas. It highlights the need for heightened clinical awareness, thorough evaluation, and advanced diagnostic tools for timely and accurate identification of uncommon parasitic diseases in children.